The invention relates to automatic transmissions for motor vehicles, particularly compound brakes having series related roller brake and friction brake portions.
A freewheeling roller brake used to anchor a reaction element of gearing for an automatic transmission is shown in U.S. Pat. No. 3,613,481, which is assigned to the assignee of this invention. The gearing of that prior art reference has inner and outer bearing races that cooperate with one another and that are mounted concentrically with respect to each other by means of support rings of C-shaped cross-section. The support rings are disposed laterally on either side of the brake rollers.
The outer bearing race of the prior art design of the '481 patent is arranged rotationally rigidly on the gearbox casing, and the inner bearing race is connected drivably to the second planet gear carrier of a Simpson-type planet gear system. The connection comprises a drum-shaped component that is engaged by a brake and that is connected to the inner bearing race by means of a radial hub. The inner bearing ring is supported and mounted on part of the drive shaft of the transmission. A disadvantage of the prior art arrangement is that the radial hub and drum-shaped component is relatively complex in its construction.
Another overrunning brake roller is disclosed in German Offenlegungsschrift (Laid-Open Specification) 34 17 703. The inner bearing race of that prior art reference (FIG. 1B) is fixed to the transmission casing, while the outer bearing race is connected drivably to the second of the two planet gear carriers of a Simpson-type planet gear system. The connection is likewise effected by means of a drum-shaped component which is engaged by a braking device and which is supported on an extended portion of the inner bearing race by means of a radial hub. Like the prior art design described above, this drum-shaped component is relatively complex in design.